Pass-throughs for use with sensor assemblies, sensor assemblies including at least one pass-through and related methods

ABSTRACT

Transducer assemblies may include a sensor and a housing including a pass-through portion comprising at least one aperture in a portion of the housing extending along a longitudinal axis of the housing and the sensor. Methods of forming transducer assemblies may include welding a first housing section of the transducer assembly to a second housing portion of the transducer assembly and forming at least one aperture in the first housing section extending along a longitudinal axis of the transducer assembly, along a chamber for holding a sensor, and through the weld.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.14/924,033, filed Oct. 27, 2015, pending, which claims the benefit ofU.S. Provisional Patent Application Ser. No. 62/074,517, filed Nov. 3,2014, the disclosure of each of which is hereby incorporated herein inits entirety by this reference.

TECHNICAL FIELD

Embodiments of the present disclosure relate to pass-throughs for usewith sensor assemblies and, more particularly, to pass-throughs utilizedto bypass one or more portions of a sensor assembly and relatedassemblies and associated methods.

BACKGROUND

Thickness shear mode quartz resonator sensors have been usedsuccessfully in the downhole environment of oil and gas wells forseveral decades and are an accurate means of determining downholepressures in widespread use in hydrocarbon (e.g., oil and gas)exploration and production, as well as in other downhole applications.Quartz resonator pressure sensors typically have a crystal resonatorlocated inside a housing exposed to ambient bottomhole fluid pressureand temperature. Electrodes on the resonator element coupled to a highfrequency power source drive the resonator and result in sheardeformation of the crystal resonator. The electrodes also detect theresonator response to pressure and temperature and are electricallycoupled to conductors extending to associated power and processingelectronics isolated from the ambient environment. Ambient pressure andtemperature are transmitted to the resonator, via a substantiallyincompressible fluid within the housing, and changes in the resonatorfrequency response are sensed and used to determine the pressure and/ortemperature and interpret changes in same. For example, a quartzresonator sensor, as disclosed in U.S. Pat. Nos. 3,561,832 and3,617,780, includes a cylindrical design with the resonator formed in aunitary fashion in a single piece of quartz. End caps of quartz areattached to close the structure.

Generally, a pressure transducer comprising a thickness shear modequartz resonator sensor assembly may include a first sensor in the formof a primarily pressure sensitive thickness shear mode quartz crystalresonator exposed to ambient pressure and temperature, a second sensorin the form of a temperature sensitive quartz crystal resonator exposedonly to ambient temperature, a third reference crystal in the form ofquartz crystal resonator exposed only to ambient temperature, andsupporting electronics. The first sensor changes frequency in responseto changes in applied external pressure and temperature with a majorresponse component being related to pressure changes, while the outputfrequency of the second sensor is used to temperature compensatetemperature-induced frequency excursions in the first sensor. Thereference crystal, if used, generates a reference signal, which is onlyslightly temperature-dependent, against or relative to which thepressure-induced and temperature-induced frequency changes in the firstsensor and the temperature-induced frequency changes in the secondsensor can be compared. Such comparison may be achieved by, for example,frequency mixing frequency signals and using the reference frequency tocount the signals from the first and second sensors for frequencymeasurement.

Prior art devices of the type referenced above including one or morethickness shear mode quartz resonator sensors exhibit a high degree ofaccuracy even when implemented in an environment such as a downholeenvironment exhibiting high pressures and temperatures. However, whenimplemented as pressure sensors, the sensors in these devices must be atleast partially exposed to the exterior environment surrounding thedevice. For example, when implemented in a downhole environment, thesensors may be exposed to pressures up to about 30,000 psi (about 206.84MPa) and temperatures of up to 200° C. Accordingly, in order to complywith such extreme pressure and temperature environments and shifts inpressure and temperature, the housings of such devices enclosing thesensors must be designed and manufactured to be substantially robust asto not fail when implemented in the field exposed to such pressures andtemperatures.

For example, where pressure transducers are required to at leastpartially expose one or more pressure sensors within the pressuretransducer to the pressure of the external environment (e.g., via afluid within the sensor), the housing of the transducer must be designedto enable the pressure sensors to be in communication with pressure ofthe external environment while still maintaining structural integrityand protecting other components of the transducer, such as, for example,reference sensors, temperature sensors, and other electronics in thetransducer from the surrounding extreme pressure and temperatureenvironments. In some implementations, it is required to passconnections, such as electrical conductors, along the length of thetransducer and past the pressure sensors from one component to anothercomponent within or external to the transducer. Thus, passing theelectrical conductors past each pressure sensor may be difficult as suchconnections must be routed through or around portions of one or morepressure housings having the pressure sensors therein and that areequipped to handle the forces from pressures and temperatures of adownhole environment.

BRIEF SUMMARY

In some embodiments, the present disclosure includes a transducerassembly. The transducer assembly includes at least one sensor and ahousing having a longitudinal axis. The housing includes a sensorhousing portion at least partially enclosing the at least one sensor ina chamber in the sensor housing portion and a pass-through portioncomprising at least one aperture in a portion of the housing extendingalong the longitudinal axis and the sensor housing portion.

In additional embodiments, the present disclosure includes a transducerassembly. The transducer assembly includes at least one sensor and ahousing having a longitudinal axis. The housing includes a sensorhousing portion at least partially enclosing the at least one sensor ina chamber in the sensor housing portion where the chamber is at leastpartially offset from the longitudinal axis of the housing and apass-through portion comprising at least one aperture in a portion ofthe housing extending along the longitudinal axis and the sensor housingportion.

In additional embodiments, the present disclosure includes a transducerassembly. The transducer assembly includes at least one pressure sensor,an electronics assembly, and a housing having a longitudinal axis. Thehousing includes a pressure housing at least partially enclosing the atleast one pressure sensor in a chamber in the pressure housing. Thepressure housing includes a thick wall portion positioned on one lateralside of the pressure housing where the thick wall portion has a lateralwidth taken in a direction transverse to the longitudinal axis of thehousing that is greater than a lateral width taken in the directiontransverse to the longitudinal axis of the housing of another wallportion of the pressure housing positioned on another lateral side ofthe pressure housing. The housing further includes an electronicshousing having the electronics assembly disposed therein and apass-through portion comprising at least one aperture in the thick wallportion of the pressure housing and extending along the longitudinalaxis of the housing and the pressure housing. The transducer assemblyfurther includes at least one electrical connection electronicallycoupled to the electronics assembly where the at least one electricalconnection extends through the at least one aperture of the pass-throughportion to the electronics assembly.

In additional embodiments, the present disclosure includes a method offorming a transducer assembly. The method includes welding a firstsection of the transducer assembly to a second section of the transducerassembly with a width of the weld selected to exceed a required width bya selected dimension, the required width selected in view of one or moreof a maximum external pressure and a maximum external temperature towhich the transducer is designed to handle during use, and forming atleast one aperture in a housing of the transducer assembly extendingalong a longitudinal axis of the housing and through the weld, the atleast one aperture exhibiting a width substantially less than or equalto the selected dimension.

In yet additional embodiments, the present disclosure includes a methodof forming a transducer assembly. The method includes welding a firsthousing section of the transducer assembly exhibiting a thick wallportion positioned on one lateral side of a chamber for receiving apressure sensor to a second housing portion of the transducer assembly,the thick wall portion of the first housing section having a lateralwidth taken in a direction transverse to a longitudinal axis of thetransducer assembly that is greater than a lateral width taken in thedirection transverse to the longitudinal axis of the transducer assemblyof another wall portion, and forming at least one aperture in the thickwall portion of the first housing section extending along thelongitudinal axis of the transducer assembly, along the chamber, andthrough the weld.

In yet additional embodiments, the present disclosure includes sensorsand related assemblies and methods of forming and operating sensors andrelated assemblies as described below.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming what are regarded as embodiments of the presentdisclosure, various features and advantages of embodiments of thedisclosure may be more readily ascertained from the followingdescription of example embodiments of the disclosure provided withreference to the accompanying drawings, in which:

FIG. 1 is a partial cross-sectional simplified schematic view of atransducer assembly in accordance with an embodiment of the presentdisclosure;

FIG. 2 is another cross-sectional simplified schematic view of thetransducer assembly shown in FIG. 1;

FIG. 3 is a partial cross-sectional view of a transducer assembly inaccordance with an embodiment of the present disclosure;

FIG. 4 is a front view of a transducer assembly in accordance with anembodiment of the present disclosure;

FIG. 5 is a partial cross-sectional view of the transducer assemblyshown in FIG. 4;

FIG. 6 is an exploded, partial cross-sectional simplified schematic viewof a transducer assembly in accordance with an embodiment of the presentdisclosure;

FIG. 7 is a partial cross-sectional simplified schematic view of thetransducer assembly of FIG. 6 shown during assembly of the transducerassembly; and

FIG. 8 is a partial cross-sectional simplified schematic view of thetransducer assembly of FIGS. 6 and 7 shown during assembly of thetransducer assembly.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings that depict, by way of illustration, specificembodiments in which the disclosure may be practiced. However, otherembodiments may be utilized, and structural, logical, andconfigurational changes may be made without departing from the scope ofthe disclosure. The illustrations presented herein are not meant to beactual views of any particular sensor, transducer, assembly, orcomponent thereof, but are merely idealized representations that areemployed to describe embodiments of the present disclosure. The drawingspresented herein are not necessarily drawn to scale unless otherwiseindicated. Additionally, elements common between drawings may retain thesame numerical designation.

Although some embodiments of sensors of the present disclosure aredepicted as being used and employed in pressure transducer assembliesutilizing one or more quartz resonator sensors, persons of ordinaryskill in the art will understand that the embodiments of the presentdisclosure may be employed in any assembly or system for measurement ofan environment external to one or more sensors where the one or moresensors are at least partially exposed (e.g., in communication with) theexterior environment.

FIG. 1 is a partial cross-sectional simplified schematic of a transducerassembly (e.g., pressure transducer 100) including a housing 101. Asshown in FIG. 1, the housing 101 of the pressure transducer 100 includesa first portion (e.g., pressure housing 102) for holding one or moresensors that are at least partially exposed (e.g., entirely exposed,exposed to the pressure and/or temperature of the exterior environment).For example, the pressure transducer 100 may include one or morepressure sensors 104 (e.g., a quartz crystal resonating sensor) disposedin a chamber 106 in the pressure housing 102 that are exposed to thepressure and/or the temperature of the exterior environment.

The chamber 106 in the pressure housing 102 may be in communication withan environment exterior to the pressure transducer 100 in order todetermine one or more environmental conditions in the exteriorenvironment (e.g., pressure and/or temperature of the exteriorenvironment). For example, the chamber 106 may be in fluid communicationwith one or more isolation elements 108 (e.g., a diaphragm assembly, abladder assembly, a bellows assembly, as well as combinations of theforegoing). In some embodiments, isolation element 108 may be configuredas a port 109 that is in communication with an exterior environment orfluid where the port 109 may be at least partially isolated proximatethe housing 101 (e.g., with a diaphragm disposed in the port 109) or ata location away from the housing 101 (e.g., along a fluid channelextending from the housing 101). The isolation element 108 acts totransmit pressure and/or temperature exterior to the pressure transducer100 to sensors within the pressure transducer 100 (e.g., via a fluidwithin the pressure transducer 100). Fluid may be disposed in thechamber 106 around the pressure sensor 104 and, optionally, in theisolation element 108 (e.g., in a bellows) to transmit the pressureand/or temperature from the exterior of the pressure transducer 100. Insome embodiments, the fluid within pressure transducer 100 may comprisea highly incompressible, low thermal expansion fluid such as, forexample, oil (e.g., a PARATHERM® or sebacate oil). The pressure andthermal expansion of the fluid may be sensed by the pressure sensor 104(e.g., a quartz crystal sensing element).

As depicted in FIG. 1 and discussed below in greater detail, thepressure sensor 104 may be positioned along a longitudinal axis L₁₀₀ ofthe pressure transducer 100. In some embodiments, one or more of thepressure sensor 104 and the chamber 106 may be partially offset (fromthe longitudinal axis L₁₀₀ of the pressure transducer 100. For example,a longitudinal axis L₁₀₄ (e.g., a centerline) of the pressure sensor 104and/or a longitudinal axis L₁₀₆ (e.g., a centerline) of the chamber 106may be laterally offset from the longitudinal axis L₁₀₀ (e.g.,centerline) of the pressure transducer 100 (e.g., in a directiontransverse to, e.g., perpendicular to, the longitudinal axis L₁₀₀). Insome embodiments, one or more of the pressure sensor 104, the chamber106, and the pressure transducer 100 may have a substantially elliptical(e.g., an ellipse) or circular (e.g., annular, cylindrical) shape and/orcross section and the one or more of the pressure sensor 104 and thechamber 106 may have a centerline that is laterally offset from acenterline of the pressure transducer 100. In other embodiments, one ormore of the pressure sensor 104 and the chamber 106 may be substantiallyaligned with the longitudinal axis L₁₀₀ of the pressure transducer 100.For example, the longitudinal axes L₁₀₄, L₁₀₆ of one or both of thepressure sensor 104 and the chamber 106 may be substantially alignedwith the longitudinal axis L₁₀₀ of the pressure transducer 100.

An electronics housing 110 is coupled to the pressure housing 102 (e.g.,via spacer 114). As depicted, the electronics housing 110 includes anelectronics assembly 112 that is at least partially isolated from thefluid within the chamber 106 in the pressure housing 102, which is incommunication with the exterior environment. The electronics assembly112 may be electrically coupled to the pressure sensor 104 in thepressure transducer 100 via electrical connections (e.g., feedthroughpins 116 that extend through the spacer 114) and may be utilized tooperate (e.g., drive) one or more of the pressure sensor 104 and toreceive the output of the pressure sensor 104.

In some embodiments, the pressure sensor 104 may be at least partiallysealed in the pressure housing 102 by another portion of the housing 101(e.g., the spacer 114). As depicted, the spacer 114 may form a bulkheadbetween the electronics housing 110 and the pressure housing 102.

At least a portion of the housing 101 of the pressure transducer 100comprises a pass-through portion (e.g., a feedthrough portion) includingone or more pass-through apertures 118 extending through a portion ofthe housing 101 (e.g., the pressure housing 102 and the spacer 114). Thepass-through aperture 118 may be used to pass a connection (e.g., one ormore electrical connections 120) past the pressure housing 102. Forexample, the electrical connection 120 may extend through thepass-through aperture 118 from another component of the pressuretransducer 100 (e.g., another sensor, another electronics assembly, apower source, etc.), and/or a component external to the pressuretransducer 100, along the longitudinal axis L₁₀₀ of the pressuretransducer 100, along the pressure housing 102 and the spacer 114, andto the electronics assembly 112 in the electronics housing 110. Such aconfiguration may enable one or more connections to be passed along thelongitudinal axis L₁₀₀ of the pressure transducer 100 while being atleast partially isolated from the pressure housing 102 (e.g., from thefluid and/or pressure sensor 104 that is at least partially exposed tothe exterior environment as discussed above).

FIG. 2 is another cross-sectional simplified schematic view of a portionof the housing 101 (e.g., the pressure housing 102) of the pressuretransducer 100 shown in FIG. 1 taken in a direction transverse to thelongitudinal axis L₁₀₀ (FIG. 1) of the pressure transducer 100. As shownin FIG. 2, the pressure housing 102 includes the pass-through aperture118 on one side of the pressure housing 102. The pressure housing 102also includes the chamber 106 for receiving the pressure sensor 104(FIG. 1). As depicted, the chamber 106 is laterally offset in thepressure housing 102. For example, the centerline of the chamber 106(e.g., which may coincide with the longitudinal axis L₁₀₆ of the chamber106) is offset from the centerline of pressure housing 102 (e.g., whichmay coincide with the longitudinal axis L₁₀₀ of the pressure transducer100). As can be seen in FIGS. 1 and 2, the pressure sensor 104 in thechamber 106 will also be offset due to the offset of the chamber 106.

In order to accommodate the pass-through aperture 118 extending throughthe housing 101, one or more portions of the housing 101 (e.g., thepressure housing 102) may include a first wall portion 122 (e.g., athick or enlarged walled portion) having a first dimension D₁₂₂ (e.g.,width, thickness, taken in a direction transverse (e.g., perpendicular)to the longitudinal axis L₁₀₀ (FIG. 1) of the pressure transducer 100)that is greater than a second dimension D₁₂₄ (e.g., width, thickness,taken in a direction transverse (e.g., perpendicular) to thelongitudinal axis L₁₀₀ (FIG. 1) of the pressure transducer 100) of asecond adjacent (e.g., opposing) wall portion 124 (e.g., a thin ornormal walled portion) of the housing 101. For example, the first wallportion 122 and the second wall portion 124 may be positioned about thechamber 106 (e.g., at opposing sides of the chamber 106) where the wallsof the pressure housing 102 extending between the first wall portion 122and the second wall portion 124 taper between the two thicknesses D₁₂₂,D₁₂₄. As discussed below in greater detail, such varying wallthicknesses may allow the pressure housing 102 to accommodate thepass-through aperture 118 on one side of the pressure housing 102 whilestill providing a minimum wall thickness surrounding the chamber 106that can withstand the external forces applied to the pressure housing102 and/or enable the required connection to (e.g., weld to) anotherportion of the housing 101 (e.g., the spacer 114 (FIG. 1)).

FIG. 3 is a partial cross-sectional view of a transducer assembly (e.g.,pressure transducer 200) that may be similar to and include the same orsimilar features of the pressure transducer 100 shown and describedabove with reference to FIGS. 1 and 2. As shown in FIG. 3, the pressuretransducer 200 may include a pressure housing 202 and one or morepressure sensors 204 disposed in a chamber 206 in the pressure housing202 that are exposed to the pressure and/or the temperature of theexterior environment. As above, the chamber 206 may be offset from alongitudinal axis L₂₀₀ of the pressure transducer 200 and may beconfigured to exhibit one or more of an elliptical, annular,cylindrical, and circular shape and/or cross section. The pressuretransducer 200 may include a cap (e.g., spacer 214 including a flangeportion 215) that is at least partially received in the chamber 206(e.g., a protrusion of the spacer 214 surrounded by the flange portion215 is received in the chamber 206) and one or more pass-through pins216 extending through the spacer 214. The spacer 214 may be coupled tothe pressure housing 202 via a welding process coupling at least theflange portion 215 of the spacer 214 to the pressure housing 202, suchas that discussed below with reference to FIGS. 6 through 8.

The chamber 206 of the pressure housing 202 may be in fluidcommunication with one or more isolation elements 208 (e.g., a diaphragmassembly, a bladder assembly, a bellows assembly, as well ascombinations of the foregoing) via channel 209. The channel 209 and thechamber 206 may be filled with a fluid (e.g., via fill port 217) thattransmits pressure and/or temperature to the pressure sensor 204 fromthe isolation element 208.

As depicted, the isolation element 208 may be housed in isolationhousing 207 that is coupled to the pressure housing 202. For example,the isolation housing 207 may be coupled to the pressure housing 202 viaa welding process similar to the welding process coupling the spacer 214and pressure housing 202 discussed below with reference to FIGS. 6through 8. In other embodiments, the isolation housing 207 may beotherwise coupled to the pressure housing 202 in any other suitablemanner (e.g., via threading).

The isolation element 208 (e.g., bellows) may be in communication withthe environment exterior to the pressure transducer 200 via chamber 211.In some embodiments, the chamber 211 may be in communication with theexternal environment (e.g., a fluid of the wellbore may fill the chamber211). In other embodiments, the chamber 211 may contain a fluid (e.g.,for transmitting pressure to the isolation element 208) that iscontained in the chamber 211 and is at least partially isolated from theenvironment exterior to the pressure transducer 200 with anotherisolation element 213 (e.g., a diaphragm) positioned in a sidewall ofhousing 202 of the pressure transducer 200.

As depicted, the pressure transducer 200 may further include anelectronics housing 210 that is coupled to the pressure housing 202(e.g., via the spacer 214). The electronics housing 210 includes anelectronics assembly 212 that is at least partially isolated from thefluid within the chamber 206 in the pressure housing 202 that is incommunication with the exterior environment. In some embodiments,housing 201 may include one or more attachment features 228 for couplingthe pressure transducer 200 to adjacent components in a downhole system(e.g., other downhole monitoring components, communication relays fortransmitting power to and data from the pressure transducer 200).

As further depicted in FIG. 3, the pressure transducer 200 may includeone or more additional sensors that are utilized along with the pressuresensor 204 to determine and compensate for environmental conditionsaffecting output of the pressure sensor 204, as well as providing areference signal. For example, the pressure transducer 200 may include atemperature sensor 230 that is at least partially isolated from (e.g.,by the spacer 214 acting as a bulkhead) the fluid within the pressurehousing 202 that is in communication with the exterior environment. Thetemperature sensor 230 is utilized to sense the temperature of theexterior environment (e.g., as is it transmitted to temperature sensor230 through the housing 201 of the pressure transducer 200 and/orthrough fluid in the pressure transducer 200) to enable compensation fortemperature-induced inaccuracies in the output of pressure sensor 204.

In some embodiments, the pressure transducer 200 may include a referencesensor 232 that is isolated from (e.g., by the spacer 214) the fluidwithin the pressure housing 202 that is in communication with theexterior environment. As known in the art, an output of such a referencesensor 232 may be utilized for comparison with other sensors (e.g., thepressure sensor 204, the temperature sensor 230, or combinationsthereof). For example, one or more of pressure-induced andtemperature-induced frequency changes in the one or more of the pressuresensor 204 and the temperature sensor 230 (e.g., in a quartz crystalresonator sensing element of the respective sensors 204, 230) may bedetected by monitoring variations in frequency of the sensors 204, 230with respect to a frequency of the reference sensor 232 (e.g., alsoincluding a reference quartz crystal resonator). Data relating tofrequency differences detected by the sensors 204, 230, 232 may bemanipulated by the electronics assembly 212 or by electrical equipmentat the surface of the wellbore to provide pressure and/or temperaturedata to an operator monitoring wellbore conditions.

At least a portion of the housing 201 of the pressure transducer 200comprises a pass-through portion including one or more pass-throughapertures 218 extending through a portion of the housing 201. Forexample, the pass-through aperture 218 may extend along the longitudinalaxis L₂₀₀ of the pressure transducer 200 through a portion of thehousing 201 at least partially exposed to an external environment (e.g.,an external pressure), such as, for example, the pressure housing 202,the isolation housing 207 and the spacer 214. As above, the pass-throughaperture 218 may be used to pass a connection (e.g., one or moreelectrical connections 120 (FIG. 1)) from another component of thepressure transducer 200 or from a component external to the pressuretransducer 200 along the longitudinal axis L₂₀₀ of the pressuretransducer 200, past and along the isolation housing 207, the pressurehousing 202, and the spacer 214, and to the electronics assembly 212 inthe electronics housing 210. Such a configuration may enable one or moreconnections to be passed along the longitudinal axis L₂₀₀ of thepressure transducer 200 while being at least partially isolated from theportions of the pressure transducer 200 exposed to the externalenvironment.

FIG. 4 is a front view of a transducer assembly (e.g., pressuretransducer 300) and FIG. 5 is a partial cross-sectional view of atransducer assembly. In some embodiments, the pressure transducer 300may be similar to and include the same or similar features of thepressure transducers 100, 200 shown and described above with referenceto FIGS. 1 through 3. As shown in FIG. 4, housing 301 of the pressuretransducer 300 may include a pressure housing 302, which may include oneor more sensors that are at least partially exposed to the exteriorenvironment as discussed below, coupled to an electronics housing 310,which may include electronics and other sensors that are at leastpartially isolated from the exterior environment as also discussedbelow.

As depicted, the housing 301 may include one or more isolation elements308 disposed on an exterior portion (e.g., wall, outer surface) of thehousing 301 (e.g., extending through a sidewall of the pressure housing302) that are also in communication with an interior portion of thehousing 301 (e.g., with chambers holding or in communication withsensors as detailed below). In some embodiments, the isolation elements308 may be diaphragms (e.g., oval diaphragms) such as those describedin, for example, U.S. Pat. No. 8,333,117, to Brown et al., thedisclosure of which is hereby incorporated herein in its entirety bythis reference.

In some embodiments, each isolation element 308 may be in communicationwith differing portions of the downhole assembly to separately monitorthe environmental conditions in the different portions. For example, oneisolation element 308 may be in communication with an environment withina string of tubular components (e.g., a production string) positioned ina wellbore annulus and another isolation element may be in communicationwith an environment in an annulus between the string in the wellboreannulus and the wellbore itself (e.g., between the string and a casingor liner string adjacent the wall of the wellbore).

As shown in FIG. 5, the pressure transducer 300 may include a pressurehousing 302 and one or more pressure sensors 304. For example, thepressure transducer includes multiple pressure sensors (e.g., twopressure sensors 304A, 304B) disposed in one or more chambers 306 (e.g.,chambers 306A, 306B) in the pressure housing 302 that are both exposedto the pressure and/or the temperature of the exterior environment. Asabove, each chamber 306A, 306B may be offset from a longitudinal axisL₃₀₀ of the pressure transducer 300 and may exhibit one or more of anelliptical, annular, cylindrical, and circular shape and/or crosssection.

The pressure transducer 300 may include one or more caps at either endof the pressure housing 302. For example, spacer 314A including a flangeportion 315A may be at least partially received in the chamber 306A andone or more feedthrough pins 316A may extend through the spacer 314A ata first end of the pressure housing 302 proximate the electronicshousing 310. Spacer 314B including a flange portion 315B may be at leastpartially received in the chamber 306B and one or more feedthrough pins316B may extend through the spacer 314B at a second end of the pressurehousing 302 (e.g., opposing the first end) proximate an end of thepressure transducer 300 that may be coupled to one or more otherdownhole components. Each spacer 314A, 314B may be coupled to thepressure housing 302 via a welding process coupling at least the flangeportion 315A, 315B of each spacer 314A, 314B to the pressure housing302, such as that discussed below with reference to FIGS. 6 through 8.

Each chamber 306A, 306B of the pressure housing 302 may be in fluidcommunication with the isolation elements 308 (FIG. 4) formed in thesidewall of the pressure housing 302 of the pressure transducer 300. Forexample, each chamber 306A, 306B may be in communication with oneisolation element 308. In some embodiments, each chamber 306A, 306B mayextend through a sidewall of the pressure housing 302 to an exterior ofthe housing 301 and the isolation elements 308 may each extend over arespective chamber 306A, 306B at the outer surface of the housing 301 toseal the chamber 306A, 306B. As above, each chamber 306A, 306B may befilled with a fluid (e.g., via a respective fill port 317) thattransmits pressure and/or temperature to the pressure sensor 304A, 304Bfrom the isolation element 308.

As depicted, the pressure transducer 300 may further include electronicshousing 310 that is coupled to the pressure housing 302 (e.g., via thespacer 314A). The electronics housing 310 includes an electronicsassembly 312A, 312B (e.g., one electronics assembly 312A, 312B for eachpressure sensor 304A, 304B) that is at least partially isolated from thefluid within the chamber 306A, 306B in the pressure housing 302 that isin communication with the exterior environment.

The electronics housing 310 of the pressure transducer 300 may includeone or more additional sensors that are utilized along with the pressuresensor 304A, 304B to determine and compensate for environmentalconditions affecting output of the pressure sensor 304A, 304B, as wellas providing a reference signal. The pressure transducer 300 may includea temperature sensor 330 that is at least partially isolated from (e.g.,by the spacer 314A acting as a bulkhead) the fluid within the pressurehousing 302 that is in communication with the exterior environment.

In some embodiments, the pressure transducer 300 may include a referencesensor 332 that is isolated from (e.g., by the spacer 314A) from thefluid within the pressure housing 302 that is in communication with theexterior environment.

At least a portion of the housing 301 of the pressure transducer 300comprises a pass-through portion including one or more pass-throughapertures 318 extending through a portion of the housing 301. Forexample, the pass-through aperture 318 may extend along the longitudinalaxis L₃₀₀ of the pressure transducer 300 through a portion of thehousing 301 at least partially exposed to an external environment (e.g.,an external pressure), such as, for example, the pressure housing 302and the spacers 314A, 314B on either side of the pressure housing 302.As above, the pass-through aperture 318 may be used to pass a connection(e.g., one or more electrical connections 120 (FIG. 1)) from anothercomponent of the pressure transducer 300 along the longitudinal axisL₃₀₀ of the pressure transducer 300, past and along the pressure housing302 and the spacers 314A, 314B, and to one or more of the electronicsassemblies 312A, 312B in the electronics housing 310. Such aconfiguration may enable one or more connections to be passed along thelongitudinal axis L₃₀₀ of the pressure transducer 300, while being atleast partially isolated from the portions of the pressure transducer300 exposed to the external environment. For example, an electricalconnection between the electronics assembly 312B and the pressure sensor304B (e.g., which electronics assembly 312B drives and monitors afrequency response of the pressure sensor 304B) may be passed throughthe pass-through aperture 318 while being isolated from the chambers306A, 306B.

FIG. 6 is an exploded, partial cross-sectional view of a transducerassembly (e.g., pressure transducer 400) that may be similar to pressuretransducers 100, 200, 300 discussed above in relation to FIGS. 1 through5. As shown in FIG. 6, the pressure transducer 400 may include apressure housing 402 and one or more pressure sensors 104 disposed in achamber 406 in the pressure housing 402 that are exposed to the pressureand/or the temperature of the exterior environment. The pressuretransducer 400 may include a cap (e.g., spacer 414 including a flangeportion 415) that may be at least partially received in the chamber 406and one or more feedthrough pins 116 extending through the spacer 414.The chamber 406 of the pressure housing 402 may be in fluidcommunication with one or more isolation elements 408 (e.g., a diaphragmassembly, a bladder assembly, a bellows assembly, as well ascombinations of the foregoing) via channel 409.

FIG. 7 is a partial cross-sectional view of the transducer assembly 400of FIG. 6 shown during assembly of the pressure transducer 400. As shownin FIG. 7, the pressure sensor 104 is received the chamber 406 in thepressure housing 402. Spacer 414 is attached to the pressure housing 402at at least the flange portion 415 surrounding a protrusion 419 of thespacer 415 that is received in the chamber 406. For example, spacer 414is welded to the pressure housing 402 (e.g., along the flange portion415) to at least partially (e.g., entirely) seal the pressure sensor 104within the chamber 406. Weld 426 (e.g., weld bead) may be disposed aboutthe pressure transducer 400 at an interface between the spacer 414 andthe pressure housing 402. In embodiments where a welded joint isimplemented, the welding process may comprise one or more of a gas metalarc welding process (MIG), a gas tungsten arc welding process (TIG),other types of fusion welding process (e.g., an electron-beam weldingprocess (EBW), laser beam welding), and other types of welding.

As depicted, the depth or thickness of the weld 426 may be selected tobe larger than is required by the environmental conditions (e.g.,pressure and/or temperature) in which the pressure transducer 400 isdesigned to operate. In other words, the depth or thickness of the weld426 may be selected to extend a distance greater than the depth orthickness that is required by the maximum pressure and/or temperature inwhich the pressure transducer 400 is designed to operate. For example,the depth or thickness of the weld 426 may be selected to extend adistance substantially equal to or greater than a thickness (e.g.,diameter) of one or more apertures in the pressure housing 402 (e.g.,aperture 418 (FIG. 8)). In some embodiments, the depth or thickness ofthe weld 426 may be selected to extend a distance substantially equal toor greater than the thickness of a first wall portion 422 (e.g., a thickwalled portion) of the pressure housing 402 and to substantially exceedthe thickness of a second adjacent wall portion 424 (e.g., a thin walledportion) of the pressure housing 402. In some embodiments, the depth orthickness of the weld 426 may be selected to extend a distancesubstantially equal to or greater than the thickness of a secondadjacent wall portion 424 (e.g., a thin walled portion) of the pressurehousing 402 plus a thickness or width of an aperture (e.g., aperture418, discussed below) formed in the first wall portion 422.

FIG. 8 is another partial cross-sectional view of the transducerassembly 400 of FIGS. 6 and 7 shown during assembly of the pressuretransducer 400. As shown in FIG. 8, after the spacer 414 is welded tothe pressure housing 402, one or more apertures 418 may be formed (e.g.,machined by drilling, milling, etc.) in and extend along the pressuretransducer 400 (e.g., along and through the pressure housing 402, thespacer 414, and a portion of the weld 426 between the spacer 414 and thepressure housing 402). As discussed above, such one or more apertures418 may be utilized to pass connections (e.g., electrical connectionspast the pressure housing 402).

In some embodiments, pressure transducers in accordance with the instantdisclosure may include methods of fabrication, orientations, quartzstructures, electronics, assemblies, housings, reference sensors, andcomponents similar to the sensors and transducers disclosed in, forexample, U.S. Pat. No. 6,131,462 to EerNisse et al., U.S. Pat. No.5,471,882 to Wiggins, U.S. Pat. No. 5,231,880 to Ward et al., U.S. Pat.No. 4,550,610 to EerNisse et al., and U.S. Pat. No. 3,561,832 to Karreret al., the disclosure of each of which patents is hereby incorporatedherein in its entirety by this reference.

As mentioned above, sensors as disclosed herein (e.g., pressure sensors)may comprise a quartz crystal sensing element. In some embodiments, sucha pressure transducer having a quartz crystal pressure sensor (e.g.,such as that described in U.S. Pat. No. 6,131,462 to EerNisse et al.)may also include a quartz crystal reference sensor and a quartz crystaltemperature sensor that are utilized in comparing the outputs of thecrystal sensors (e.g., via frequency mixing and/or using the referencefrequency to count the signals from the other two crystals) fortemperature compensation and to prevent drift and other pressure signaloutput anomalies. In other embodiments, one or more of the sensors(e.g., the temperature sensor) may comprise an electronic sensor (e.g.,a silicon temperature sensor using, for example, integrated electroniccircuits to monitor temperature rather than a sensor exhibitingtemperature-dependent variable mechanical characteristics (e.g.,frequency changes of a resonator element) such as a quartz crystalresonator). For example, the sensor configurations may be similar tothose described in U.S. patent application Ser. No. 13/934,058, filedJul. 2, 2013, the disclosure of which is hereby incorporated herein inits entirety by this reference, which application describes the use ofan electronic temperature sensor in a pressure transducer.

In yet additional embodiments, the pressure sensors may comprise adual-mode sensor configured to sense both pressure and temperature, forexample, such as those described in U.S. patent application Ser. No.13/839,238, filed Mar. 15, 2013, now U.S. Pat. No. 9,528,896, issuedDec. 27, 2016, the disclosure of which is hereby incorporated herein inits entirety by this reference.

Embodiments of the present disclosure may be particularly useful inproviding transducers (e.g., pressure transducers) that are at leastpartially exposed to the exterior environment and still enable theability to pass connections from one component of the transducer orbetween multiple transducers or other components through (e.g., within)the housing of the transducer. Conventionally, such connections arerequired to be passed around one or more portions of a housing of thetransducer (i.e., outside and external to the housing of the transducer)that are exposed to the exterior environment (e.g., a pressure housing)due to the structural and/or sealing constraints imposed by suchtransducers. As will be appreciated, such transducers including externalconnections generally are required to have relatively larger diametersor cross-sectional areas than transducers in accordance with the instantdisclosure that enable the ability to pass conductors through aninternal pass-through of the sensor. In downhole applications, such apass-through portion in a transducer housing may enable the overall sizeof a transducer assembly to be reduced, enabling other components of adownhole tool to utilize the space and/or enabling more efficientproduction of current, smaller wellbore diameter wells as well asexploration of new, more challenging formations using so-called“slimhole” drilling techniques with small diameter drilling strings andbottomhole components. For example, relatively smaller transducers alsoenable the ability to pass wires past the transducer between componentsabove and below such transducers when disposed in a drill string in waysthat were not possible before with conventional sized transducers.

While the disclosure may be susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and have been described in detail herein.However, it should be understood that the disclosure is not intended tobe limited to the particular forms disclosed. Rather, the disclosureencompasses all modifications, variations, combinations, andalternatives falling within the scope of the disclosure as defined bythe following appended claims and their legal equivalents.

1. A method of forming a transducer assembly, the method comprising:forming a weld bead between a first section to a second section, alateral width of the weld bead selected to exceed a required width by aselected dimension, the required width selected in view of at least oneof a maximum external pressure or a maximum external temperature underwhich the transducer is designed to operate during use; and forming atleast one aperture in a housing of the transducer assembly extendingalong a longitudinal axis of the housing and through the weld bead, theat least one aperture exhibiting a width substantially less than orequal to the selected dimension.
 2. The method of claim 1, furthercomprising extending at least one electrical connection coupled to anelectronics assembly of the transducer assembly through the at least oneaperture in the housing of the transducer.
 3. A method of forming atransducer assembly, the method comprising: welding a first housingsection of the transducer assembly exhibiting a thick wall portionpositioned on one lateral side of a chamber for receiving a pressuresensor to a second housing section of the transducer assembly, the thickwall portion of the first housing section having a lateral width takenin a direction transverse to a longitudinal axis of the transducerassembly that is greater than a lateral width taken in the directiontransverse to the longitudinal axis of the transducer assembly ofanother wall portion; and forming at least one aperture in the thickwall portion of the first housing section extending along thelongitudinal axis of the transducer assembly, along the chamber, andthrough the weld.
 4. The method of claim 3, further comprising:extending at least one electrical connection through the at least oneaperture in the first housing section; and electrically coupling anelectronics assembly of the transducer assembly with another componentwith the at least one electrical connection.
 5. The method of claim 4,wherein electrically coupling an electronics assembly of the transducerassembly with another component with the at least one electricalconnection comprises electrically connecting the electronics assembly ofthe transducer assembly with another pressure sensor of the transducerassembly.
 6. The method of claim 1, further comprising defining apressure housing in the transducer assembly at a location offset from acentral axis of the transducer assembly.
 7. The method of claim 6,further comprising disposing a pressure sensor in the pressure housingthat is isolated and laterally spaced from the at least one aperture. 8.The method of claim 7, further comprising enclosing and sealing thepressure sensor in the pressure housing with the weld.
 9. The method ofclaim 3, further comprising positioning the chamber such that alongitudinal axis of the chamber is laterally offset from thelongitudinal axis of the transducer assembly and the longitudinal axisof the transducer assembly passes through the chamber.
 10. The method ofclaim 3, further comprising selecting each of the first housing sectionand the chamber of the first housing section to comprise a substantiallyelliptical or circular shape, and wherein a centerline of the firsthousing section is laterally offset from a centerline of the chamber ofthe first housing section.
 11. The method of claim 3, further comprisingforming the weld to exhibit a substantially constant lateral width. 12.The method of claim 11, further comprising selecting the lateral widthof the weld taken in a direction transverse to the longitudinal axis ofthe transducer assembly to be greater than or equal to a width selectedin view of at least one of a maximum external pressure or a maximumexternal temperature under which the transducer assembly is designed tooperate during use plus a width of the at least one aperture in thethick wall portion of the first housing section.
 13. The method of claim3, further comprising defining the first housing section to contain atleast two pressure sensors in respective chambers.
 14. The method ofclaim 13, further comprising extending the at least one aperture in thethick wall portion of the first housing section along each chamberhousing the at least two pressure sensors.
 15. A method of forming atransducer assembly, the method comprising: disposing at least onepressure sensor in a pressure housing, the pressure housing comprising athick wall portion positioned on one lateral side of the pressurehousing, the thick wall portion having a lateral width taken in adirection transverse to a longitudinal axis of the pressure housing thatis greater than a lateral width taken in the direction transverse to thelongitudinal axis of the pressure housing of another wall portion of thepressure housing positioned on another lateral side of the pressurehousing; and electrically connecting the at least one pressure sensor toan electronics assembly with at least one electrical connectionextending through at least one aperture in the thick wall portion of thepressure housing along an entirety of the one lateral side of thepressure housing.
 16. The method of claim 15, further comprisingselecting the at least one pressure sensor to comprise a quartzresonator pressure sensor.
 17. The method of claim 15, furthercomprising sealing the at least one pressure sensor in the pressurehousing with a weld positioned at a first end of the pressure housing.18. The method of claim 17, further comprising defining at least aportion of a lateral width of the weld taken in a direction transverseto the longitudinal axis of the pressure housing is selected to equal awidth selected in view of at least one of a maximum external pressure ora maximum external temperature under which the transducer assembly isdesigned to operate during use plus a width of the at least one aperturein in the thick wall portion of the pressure housing.
 19. The method ofclaim 15, further comprising disposing at least another pressure sensorin a chamber of the pressure housing.
 20. The method of claim 20,further comprising electrically connecting the at least another pressuresensor to the electronics assembly with the at least one electricalconnection extending through at least one aperture in the thick wallportion of the pressure housing.